Facing the Consequences of Mutation

When a gene mutates and that mutation is passed along to the next generation,
the new, mutated version of the gene is considered a new allele. Alleles are
simply alternative forms of genes. For most genes, many alleles exist. The
effects of mutations that create new alleles are compared with the mutation’s
physical (phenotypic) effects. If the mutation has no effect, it’s considered silent.
Most silent mutations result from the redundancy of the genetic code. The code
is redundant in the sense that multiple combinations of bases have identical
meanings